Improvement in slide-valves



BRAHAM un ivnncwar,` oF NEW volta-n. Y.-

` Letter-s Patent N y. 100,625, da-fed llIa-rchy 8, 1870.

'IMPaovnMEN'r 1N SLIDE-VALVS.

The. Soheule referred. to in these Lett-ers Patent and making peut of the same.

To fall whom it 'may concern Be itknown that I, ABRAHAM HnMINGwAYfof thc city, county, and State otNew York, have invented a new and useiul Improvement in Relieving Slide-Valves,

of which the following is a' full, clear, and exact decription, reference being had to-the accompanying `Figure 1 represents a central transverse section of a slide-valve and its seat, constructed in accordance withmynvention';

4Figure, a plan of the valve-seat;

Figure 3, a face view of the valve; and' 11i ure' 4, a longitudinal section of said valve.

drawing forming part of this' specification, and in4 Similar 'letters 'of' reference 4indicate correspomling parts.

`My improvement has Areference" to slide-valves, in

lwhich the same are relieved of the greaterv portion of the steam pressure on their' backs d-ue tothe area under exposure to thelinid or vapor; and

The invention consists, first, in a cer-tain combination with a loose or piston-like back tothe valve of a loose curved rocker, L rranged to rest u pon the valvef.

seat or other plain bearing-surface, and supportingo` carrying the loose baok,"whe1"eby the valve is relieved of sliding friction `0n its seat, and a smooth and easy yet close action is secured to the valve, that, by means oi' the looserocker, requires but little power to move or reciprocate it; and

llfhe invention furtherconsists, under suoli a constructionaud arrangement-of parts, in providing` the..

rocker with teeth and its seat 01"bearing-surface with corresponding indentations, to give a guiding and steadying action to the valve.

Referringto the accompanying drawing- A-represents the slide-valve, of an culinary hollow. vor bonnet-like shape, and iitted with a looseor pistonlike back, B, which may he providedwith packing at or around itsedges, forced ont .by springs or by steam admitted through orifices in the back, or by both forces combined. 4vAlthough here shown oi' parallelo- 'gramic form, said 'loosebaclc as also, if preferred, the

valve-body generally, may be of circular o1' .any other desired shape. D is thevalve-seat,over which 'thefvalvc reciprocates or travels, to cover and un'covc' alternatelythe npposits steam-ports c uf,fo`r the purpose of establishing their communication successively with the steaml in the -valve-chcstand with theexhaust-cavity in the valve that communicates with 'theexhaust-port or passage b, as in otherslidcvalve arrangements.

The loose or piston-like back B of thc valve is sunv ported or carried bya loose rocker, C, of arched or other plain bearing surface D.

curved form, where it rests upon the valve-seat or.:

This rocker is arranged to-rnn centrally under the back 13,and is ina loose or free rocking connection with it, as at c c. Bythis Inode of sustaining the' loose back to the valve, a free rolling support is se- 'cured to it during the play 01' .reciprocating action 'of the valve, which relieves-the'latter vof friction or slid- 'ing pressure onits seat, and allows of the valve being vworked withor by'very little power, yet in no way in-` .t'elfe'res with its closeit.

'E arebrackets brcapsfor holding the rocker in p lace "when lifting the valve from its seat, but not serving as bearings to theV rocker inthe operation of it.

If de'sired--and such provision is especially applicable to vertical or other than horizontal positionsof lthe valve-the curved traveling-surface vof the rocker C may be constructed with teeth (l, arranged to gear with vor enter indentations e inthe valve-seat or bearingsuriace D, as said rocker, in oir-during the move- .ment o ithevalvc, rolls or `travels with the'mouth portion of it'ssuriace rest-ing on the plain surface oi' the seat, to carry the load produced by the pressure ofthe steamon the, back B, while the teeth d serve to guide` vor steady the rocker and valve, and to prevent thel valve from being twisted or tipped away from its seat, either as caused by water in the cylinder or as due to some particular position of the valve.

Although the invention is here described as an improvement in slide-valves applicablewto the working of steam, it, of course, is equally applicable to valves used to control water, o1', in fact, any tlnid, gas, or vapor.

What is here claimed, and desired to be secured by Letters Patent, is-

1. rlhe combination wit-h the loose or piston-like back B tothe valve, of the loose rocker C, of arched or curved form, where it bears upon the valve-seat or other plain supportiiig-surface D', and arranged in relation to and-in connection with said back, for 

